AQUEOUS ANIONIC POLYURETHANE DISPERSIONS

Abstract: Improved aqueous anionic polyurethane dispersions with a high crystallization rate, low heat activation temperature, high green strength, stability at low pH, which show good compatibility with other water based polymers and with crosslinkers. The aqueous anionic polyurethane dispersions have high heat resistance after curing or blending with a crosslinker.

Description: AQUEOUS ANIONIC POLYURETHANE DISPERSIONS Background of the Invention This invention relates to new aqueous polyurethane dispersions having high crystallization rates, good stability at low pH and high heat resistance. These arc important basic properties for improved polyurethane dispersions, particularly for adhesive applications. Description of the Prior Art A. Sulfonated aqueous polyurethane dispersions Wolfgang Kebcrlc and Dieter Dictcrich, Canadian Pat. 764,009 (July 25, 1967) disclose aqueous polyurethane dispersions prepared from hydroxy-and carboxy-sulphonic acids, aminosulphonic acids, and the hydroxy, mcrcapto-and amino-carboxylic and sulphonic acids, polycarboxylic and polysulphonic acids include also the addition products (which may be saponified) of unsaturated acids and unsaturated nitrilcs, of cyclic dicarboxylic acid anliydrides, of sulphocarboxylic acid anliydrides, the addition products of reaction products of defines with sulphur trioxidc such as carbyl sulphate, of cpoxypropanc-sulphonic acid of sultoncs such 1,3-propancsultonc, 1,4-butancsultonc, 1,8-naphthosultonc, of disulphonic acid anliydrides to aliphatic and aromatic amines. Dieter Dictcrich and Otto Bayer, U.S.Pat. 3,479,310 (Nov. 18, 1969) disclose aqueous polyurethane dispersions based on hydroxy-and carboxy-sulphonic acids, and aminosulphonic acids as described in Canadian Patent 764,009. Hans Ludwig Honig, Gerhard Ballc, Wolfgang Kcbcrle, and Dieter Dietcrich, U.S. Pat. 3,705,164 (Dec.5, 1972) disclose sulfonated aqueous polyurethane dispersions based on mixtures of cthylencdiamine and 1,3-propane sultone. Dieter Lesch and Wolfgang Kcberle, Canadian Pat. 928323 ( June 12, 1973) disclose sulfonated aqueous polyurethane dispersions based on thc sodium salt of N-(2-aminocthyl)-2-aminocthanesulphonic acid. The patent also relates to a process for preparation of the diaminc sulfonate. It was mentioned in this patent that Belgian Patent Specification No. 673,432 (March, 1966) to Kcberle et al. discloses sulfonated aqueous polyurethane dispersions based on 2,4 diaminobenzene sulphonic acid. However, the polyurethane dispersions produced from these aromatic diaminosulphonic acids undergo discoloration on exposure to light. It was also mentioned that the process for the preparation of aliphatic diaminosulphonic acids whose salts arc suitable for use as anionic structural components for light-fast polyurethane dispersions arc already known, these known processes either entail considerable expenditure in apparatus or involve the use of physiologically very dangerous starting materials (reaction of sultone with amines). Harro Witt and Dieter Dictcrich, U.S. Pat. 3,870,684 (Mar. 11, 1975) disclose aqueous polyurethane dispersions based on an adduct of 1 ,3-propancsultone and ethylenediamine (sultone-diamine adducts are described in German Auslegcschrift No.1,200,318). It also mentioned hydroxy- and carboxy-sulphonic acids, and aminosulphonic acids which described in Canadian Patent 764,009 may be used to prepare aqueous polyurethane dispersions. Helmut Reiff, Wolfgang Wcnzel, Jurgcn Grammel, and Dieter Dictcrich, U.S. Pat. 4,108,814 (Aug.22, 1978), disclose aqueous polyurethane dispersions based on sulphonate diols have the general formula: H- (0-CH-CH 2 ) „-0- (A) 0 -CH- (B) p -0- (CH 2 -CH-0) m -H * (CH 2 ) q R S0 3 "X* In the examples, the following sulfonated did and diaminc were used to prepare aqueous polyurethane dispersions: (1) Sodium salt of propoxylatcd 3-hydroxy-2-hydroxymethyl propanc-sulphonic acid-1 (molecular weight 428) (AD); and (2) Sodium salt of cthylcnediamino-2-cthancsulphonic acid (AAS) Peter H. Markusch, James W. Rosthauscr, and Michael C. Bcatty, U.S.Pat. 4,501,852 (Feb.26, 1985), disclose aqueous polyurethane dispersions based on 70% solution in toluene of propoxylatcd sodium salt of 1 ,4-dihydroxy-2-butanc sulfonic acid having a molecular weight of 430 ("sulfonatc diol"). Otto Lorenz, Helmut Rciff, and Dieter Dictcrich, Europaische Pat. 0 222 289 A3 (May 21, 1987), used sodium salt of 2-aminocthyl-2 aminocthancsulfonic acid (Na-AAS) and dimcthylsulfonatc to prepare polyurethane dispersions. Rudolf Hombach, and Helmut Rciff, U.S.Pat. 4,663,337 (May 5, 1987) used sodium salt of N-(aminoethyl)-aminoethanc sulfonic acid to prepare polyurethane dispersions. Wolfgang Henning, Rudolf Hombach, Walter Mcchcl, and Manfred Dollhauscn, U.S.Pat. 4,870,129 (Scp.26, 1989), used sodium salt of N-(2-aminocthyl)-2-aminocthanc sulfonatc acid (AAS salt) to prepare polyurethane dispersions. The patent also states "Anionic or potentially anionic starting components include, for example, aliphatic diols containing sulphonate groups according to DE-OS No. 2,446,440 or DE_OS No. 2,437,218, diols and/or diaminosulphonatcs containing carboxylate groups or groups capable of being converted into carboxylate groups as described in CA-PS 928,323, e.g. the sodium salt of N-(2-aminoethyl)-2-aminocthanc sulphonic acid". Wolfgang Hcnning, Harald Pctcrscn, and Gerhard Moormann, U.S. Pat. 4,921,842 (May 1, 1990) used a propoxylatcd adduct of but-2-cnc-l,4-diol and NaHS0 3 (Mw 430: 70% in toluene) to prepare polyurethane dispersions. The patent states that "the anionic synthesis components include the aliphatic diols containing sulfonatc groups according to DE-OS No. 2,446,440 (U.S. Pat.No.4, 108,814) or DE-OS No. 2,437,218, diols and/or diamines containing sulfonatc or carboxylate groups or sulfonic or carboxylic acid groups convertible into sulfonatc or carboxylate groups of the type described in CA-PS No. 928,323, such as the sodium salt of N-(2-aminocthyl)-2-aminocthanc sulfonic acid". Svcn H.Ructman and Jogindcr N. Anand, U.S.Pat. 4,895, 894 (Jan. 23, 1990), describe "Illustrative but non-limiting the compounds containing a potential anionic (ionic) group arc ... 1,7 dihydroxynaphthalcnesulfonic acid-3 (sodium salt, potassium salt, tricthylammonium salt),l,8-dihydroxynaphthalcncdisulfonic acid-2,4 (sodium salt, potassium salt, tricthylammonium salt), 2,4 diaminotolucnesulfonic acid-5 (sodium salt, potassium salt, tricthylammonium salt), the sulfonatc diols described in U.S. Pat. No. 4,108,814". Jurgen Fock and Dictmar Schcdlitzki, U.S. Patent No. 5,001,189 (March 19, 1991), disclose an aqueous polyurethane dispersion based on a polyol component which is a polyoxyalkylene ether with an average molecular weight of 400 to 10,000 and having at least two terminal hydroxyl groups and at least one -SO 3 X group. A sulfonated polycthcr polyol is disclosed. B. Polyurethane Dispersions based on Diisocyanate Mixtures Wolfgang Hcnning, Rudolf Hombach, Walter Meckcl, and Manfred Dollhausen, U.S.Pat. 4,870,129 (Sep. 26, 1989), disclose polyurethane dispersions based on mixtures of hexamethylenc diisocyanate with Q(NCO) 2 in which Q denotes a divalent aliphatic hydrocarbon group with 4-12 carbon atoms or a divalent cycloaliphalic hydrocarbon group with 6-15 carbon atoms. Herbert Fisch and Lothar Macmpcl, DE 40 24 567 Al, disclose polyurethane dispersions based on mixtures of hexamethylenc diisocyanate and toluene diisocyanate. Hans Bauricdcl, Wolfgang klauck, and Gunthcr Hcnkc, PCT/EP92/00560 (26/11/92) (DE 40 24567 Al) and (DE 41 09 477 Al) (Sep. 24, 1992) disclose aqueous polyurethane dispersions based on mixture of tctramcthylxylylcnc diisocyanate (TMXDI) with hcxamcthylcne diisocyanate (HDI), isophorone diisocyanate (IPDI), 1,3-xylylcnc diisocyanate (XDI), 2,2,4-trimcthyl-l,6-hexanc diisocyanate (TMDI), toluene diisocyanate (TDI), 4,4'-diphcnylmcthanc-diisocyanatc (MDI) and dicyclohcxylmcthanc 4,4- diisocyanate (H I2 MDI). C. Crystallization of Polyurethane Dispersions Lani S. Kangas and Charles W. Stobbic IV, European Pat. 0 344 912 A3 (06/12/1989), disclose moisture curable and hot melt polyurethane based on crystalline or scmicrystallinc polyester diols having melting points between 30°C and 80°C. The polyurethane composition exhibits improved crystallization rates and posses high green strength. Palidia K. Abeywardcna and Pak T. Leung, WO 92/02568 (Feb.20, 1992), disclose polyurethane dispersions based on a crystalline oligomcric or polymeric polyol. Dispcrcoll KA-8464, an aqueous polyurethane dispersion product of Bayer Corporation and Miles (a Bayer USA, Inc. Company), based on HDI and IPDI has a high crystallization rate and stability at low pH levels, but has medium heat resistance. U-42, another Bayer aqueous polyurethane dispersion product has high heat resistance, but a low crystallization rate. D. Sulfonated Anionic Polyurethane Dispersions Helmet Rciff, Wolfgang Wenzel, Jargcn GRammel and Dieter Dieterich, U.S. Pat. 4,108,814, disclose the use of sulfonatc polyctlier diols to prepare polyurethane dispersions. Wolfgang Hcnning, Rudolf Hanbach, Walter Mcckcl and Manfred Dollhauscn, U.S. Pat. 4,870,129, disclose the use of sulfonatc diaminc as a chain extender in preparing polyurethane dispersions. Summary of the Invention This invention relates to an improved polyurethane prepolymcr and aqueous polyurethane dispersions (PUDs) made therefrom, the dispersions having a high crystallization rate, good quality stability at low pH and high heat resistance. Accordingly, the invention provides aqueous anionic polyurethane dispersions made from a prepolymer which is the reaction product of a sulfonated polyester polyol and/or a sulfonated polyester polyol mixed with dimethylol propionic acid (DMPA) and/or a sulfonated polyester polyol mixed with another polyester polyol and DMPA and/or a sulfonated polyester polyol mixed with a polyctlier polyol and DMPA and/or a sulfonated polyester polyol mixed with another polyester polyol and a polyedier polyol and DMPA, and/or mixtures of any or all of the foregoing, reacted with hcxamethylene diisocyanate (HDI) or HDI mixed with tetramcthylxylylene diisocyanate (TMXDI) and/or HDI mixed with an aromatic diisocyanate e.g., toluene diisocyanate (TDI), 4,4'-diphcnylmcthanc diisocyanate (MDI), or the like, and/or HDI mixed with other aliphatic diisocyanate e.g., isophoronc diisocyanate (IPDI), dicyclohexylmethane 4,4-diisocyanatc (H 12 MDI), or the like. The prepolymcr is then dispersed in water with a tertiary amine e.g. triethylaminc (TEA) or if made in a salt form such as a sodium salt (as exemplified in some of the Examples below) TEA is not necessary. These arc considcrcd equivalents. The prepolymcr is also chain-modified i.e., chain extended and/or chain terminated. Suitable chain extenders are: ethylenediamine or 1 ,4-butancdiol or urcido diamine (imidazolidinonc diamine) or N-isodecyloxypropyl-l,3-diaminopropanc (DA-14 from Exxon). Suitable chain terminators arc: taurinc (2-aminocd anesulfonic acid) or its sodium salt, or cthanolamine or iscthonic acid (2-hydroxyclhanesulfonic acid) or its sodium salt. Mixtures of the extenders and terminators may also be used as exemplified in some of the Examples below. Chain extenders and chain terminators arc herein referred to collectively as chain modifiers. Detailed Description of lhc Invention In preferred embodiments, the present invention provides aqueous anionic polyurethane dispersions with high crystallization rates, low heat activation temperature and high green strength. These aqueous anionic polyuretliane dispersions are stable at low pH (e.g. 5-7). Also diese aqueous polyuretliane dispersions exhibit a high degree of compatibility not only with other water-based polymers (e.g. vinyl acetate emulsion), but also with crosslinking agents (e.g. Bayer/Miles' Dcsmodur DA). These aqueous polyuretliane dispersions also have high heat resistance after curing or blending with a crosslinker. HIGH CRYSTALLIZATION RATE POLYURETHANE DISPERSIONS PolyureUianc generally consists of a hard segment (isocyanatc and chain extender) and a soft segment (polyol). European Pat. 0 344 912 A3 and WO 92/02568 disclose tiiat the crystallization of polyurcdiane dispersions depends on the structure, composition and molecular weight of the polyol component. It would therefore seem from the prior art that crystallization rate docs not depend on die hard segment crystallization but on the soft segment crystallization. Uncxpectedly, it has been found in the compositions of the present invention that the crystallization rate of these polyurethane dispersions depends on the structure of the diisocyanate (hard segment). Such polyurethane dispersions according to the invention include, in some embodiments, polyester polyol, for example Rucoflcx 105-55 (a hcxancdiol adipatc polyol, Eq.wt. 996, available from Ruco Polymer Coiporation), dimethylol propionic acid (DMPA), hexamethylenc diisocyanate (HDI), tctramcthylxylylene diisocyanate (TMXDI), Tricthylaminc (TEA) if not in salt form, and ethylene diamine/cthanolaminc (EDA/EA). The crystallization rates of several such compositions arc shown in Table 1. Table 1. Crystallization Rate and Ratio of HDI/TMXDI TMXDI/HDI DSC First Run DSC Second Run Cry. Rate* (Molar) Heat (Cal./G) Heat (CalJG) %) 1/0 12.6 0 0 0.8/0.2 17.4 0.4 2.3 0.5/0.5 10.79 6.15 57.0 0.4/0.6 15.9 9.95 62.6 0.33/0.66 11.4 8.4 73.7 0/1 10.5 8.5 80.1 NP-4041 11.5 0 0 (H.B. Fuller PUD based on TMXDI and butanediol adipate polyol and EDA/EA/DETA (diethylene- driamine) chain extender KA-8464 13.7 10.1 73.7 (Bayer/Miles 16.5 11.4 69.1 PUD based on HDI/IPDI and polyester polyol) * Crystallization rate = DSC Second Run Hcat/DSC First Run Heat DSC testing: The samples were heated from -40 to 140 degrees C at 10 degrees C/minute. The resulting thermographies arc "first Run". The samples were then quench cooled and reheated at 10 degrees C/minute to produce the "Second Run" thermographies. The crystallization rates of PUDs based only on TMXDI (e.g. NP-4041) and based only on HDI were 0 and 80%, respectively as seen in Table 1. The crystallization rale of KA-8464 as shown in Table 1 was about 70%, close to tiiat of a PUD based on a 2/1 molar ratio of HDI/TMXDI, but KA-8464 is based on HDI/IPDI. From this it can be seen that aqueous polyurethane dispersions based on HDI and its mixtures with other diisocyanate may, according to the invention, be synthesized with varying crystallization rates, depending on die ratio of HDI to die other diisocyanatc(s). The ratio may range from 100/0 to 0/100 by weight, preferably from 100/0 to about 50/50. Bauricdel et al., PCT/EP92/00560 (26/11/92) (DE 40 24567 Al), disclose aqueous polyurethane dispersions based on one isocyanatc component consisting of at least 20% by weight TMXDI, and other diisocyanatcs (HDI, IPDI, XDI, TMDI, TDI, MDI and H 12 MDI). TMXDI, al least 20% by weight in its mixture widi other diisocyanatc(s) is used to decrease die prepolymcr viscosity made from the diisocyanate mixture, so a low solvent or even a solvent free process can be used to prepare d e prepolymcr of the patent. In d e present invention, however, TMXDI in its mixture widi HDI is used to adjust the crystallization rale of d e resulting polyurcd anc dispersions because the amount of TMXDI used was unexpectedly found to be inversely proportional to the crystallization rate of die resulting pdyurediane dispersions. The use of smaller amounts of TMXDI down to zero produces a higher crystallization rate. It was also unexpectedly found, according to the invention, that die crystallization rate of the polyurcdianc dispersions of the invention also depends on the ratio of chain extender, e.g. ethylene diamine (EDA) to the chain terminator, e.g. ethanolamine (EΛ) used. The crystallization rate for several compositions arc shown in Table 2. Tablc 2. Crystallization Rate and Ratio of EDA/EA PUD Samples #4133-7 #4133-8 #4133-9 Rucoflcx 105-55 64.38 65.59 66.41 (hexancdiol adipatc polyol Eq. Wt. 996) DMPA 4.35 4.39 4.45 TEA 6.22 6.29 6.37 TMXDI 8.54 8.64 8.75 HDI 11.44 11.57 11.71 EA 4.59 2.36 0.43 EDA 0 1.16 1.88 Crystallization 64.64 75.96 84.18 Rate (%) In Table 2, PUD samples #4133-7, #4133-8 and #4133-9 have nearly same contents of DMPA, TEA, TMXDI and HDI, but different ration of EDA/EA in their compositions. These samples exhibited much different crystallization rates. Therefore, the synthesis aqueous polyurethane dispersions wid high crystallization rate depends not only on ratio of HDI to odicr diisocyanate, but also on ratio of chain extender to chain terminator. The ration may vary from a chain extender/chain terminator ration of 100/0 to 0/100, preferably from about 50/50 to about 100/0 by weight. Examples of useful chain extenders include aliphatic, cycloaliphatic, and aromatic diamines, like ethylenediamine, hexamcthylcncdiaminc, 1,4-cyclohcxylcncdiaminc, pipcrazinc, N- mcdiylpropylcncdiaminc, diaminophcnylsulfonc, diaminodiphcnylcd cr, diaminodiphcnyldimcthylmcthanc, 2,4-diamino-6-phcnyltriazinc, isophoronediamine, dimcr fatty acid diamine, N-isodccycloxy propyl-1,3- diaminopropanc (DA-14), imidazolidinonc diamine (urcido diamine). Examples of useful chain terminators include aminoalcohols, like cdianolamine, propanolaminc, butanolaminc, N-mcthylcdianolaminc, N-mcd yl- isopropanolaminc, taurine and isethionic acid. HEAT ACTIVATION AND GREEN STRENGTH In heat activation process, the polyurethane dispersion adhesive is applied to the substrate and after complete evaporation of water the layer of adhesive applied is converted into an adhesive state by die action of heat. Good adhesives should exhibit low heat activation temperature and high green strcngdi. Generally, polyurethane adhesive having high crystallization rate should have low heat activation temperature and high green strength. U.S.Pat. 4,870,129 discloses that polyurethane dispersions based on HDI/IPDI exhibited low activating temperature and high heat resistance. Unexpectedly, it has been found diat polyurethane dispersions of the invention based on mixtures of HDI with other diisocyanates do not always have low activating temperature and high heat resistance. Heat activation temperature and green strcngdi not only depend on crystallization rate, but also depend on molecular weight of polyurethane. In this invention, it has been found d at pdyurediane dispersions based on molar ratios * of HDI/TMXDI greater than 2/1 have high a crystallization rate, but have much different heat activating temperature and green strength. The results arc shown in Table 3 for several compositions. *In terms of wt, die molar ratio is: HDI/TMXDI 2/1 (molar ratio) = (2/84)/(l/122) (weight ratio) = 3/1 (weight ratio). Tablc 3. Crystallization Rate and Heat Activation PUD Samples #2 #36 #24 #37 #7 #44 #48 #8 Cry Rate (%) 0 54 56 60 65 66 75 76 Heat Activation (T-pccl, Kg) 125 °F 1.3 0.3 0.3 0.4 0 0.4 5.9 0 150°F 3.5 0.2 0.3 0.4 0 3.3 7.7 0 175°F 4.8 0.4 0.4 2.2 0 9.3 11.8 0 200 °F 6.2 0.3 0.4 5.3 0 10.5 11.9 0 Film Brittle* 3 4 4 3 5 2 1 5 * Film brittle: 1 ■ > 5 Minor Serious Table 4. Compositions for samples in Table 3 PUD HDI/TMXDI EDA/EA Cry. Rate Film Brittle Samples (Mol %) (Mol %) (%) #2 0/100 50/50 0 3 #24 67/33 50/50 54 4 #37 67/33 EA/Taurine 56 4 #7 67/33 0/100 65 5 #44 83/17 100/0 66 2 #48 83/17 80/20 75 1 #8 67/33 50/50 76 5 In view of the results shown above, it can be seen dial the present invention provides aqueous polyurethane dispersions which have low heat activating temperature and high heat resistance based on HDI and its mixturc wid odicr diisocyanate (crystallization rate), and EDA and its mixtures with chain terminators (crystallization rate and molecular weight). Surprisingly, it was found that carboxylalcd polyurcd anc prcpolymers widi high crystallization rate and low heat activation temperature based on HDI or HDI mixture with other diisocyanate, polyester polyol and DMPA cannot be dispersed into water. A large particle size dispersion wid precipitation always occurs. On the olhcr hand, when sulfonated polyurethane dispersions of die invention with high crystallization rate and low heat activation temperature were prepared (sulfonic acid is a stronger acid in comparison widi carboxylic acid) die dispersions were found to have higher solubility in water in comparison with carboxylic acid based dispersions. STABILITY AT LOW PH Usually cationic and nonionic polyurethane dispersions have low pH (less d an 7) stability, and anionic polyurethane dispersions arc stable only at higher pH (greater dian 7). U.S.Pat. 4,870,129 discloses that sulfonated pdyurediane dispersions can be stable at a pH of 5-7. A sodium salt of N-(-2 an inoethyl)-2-aminoedιanc sulphonic acid (AAS salt) was used as a chain extender to prepare die sulfonated pdyurediane dispersions. A prepolymer containing sulfonate groups could not be prepared by this process. In addition, a large quantity of acetone was used to dilute die non-sulfonatcd prepolymcr before adding the sulfonatc diamine chain extender due to die high reactivity of the sulfonatc diamine with diisocyanate. Another U.S.Pat. 4,108,814 uses sulfonate diols (sulfonated polyedicr polyols) to prepare sulfonated polyurethane dispersions. These sulfonate diols were used to prepare prepolymers containing sulfonatc groups, but diese sulfonatc diols contain ether bonds which should decrease the crystallization of die resulting polyurethane dispersions. In die present invention, however, new sulfonated polyester polyols were used to syndicsizc sulfonated aqueous polyurcd anc dispersions. Sulfonated polyester polyols were prepared from diacids, diols and sulfonate diacids and/or sulfonate diols. Aromatic and aliphatic sulfonatc diacids and diols were used, and comprised 1-10% content of the resulting sulfonated polyester polyols. Preferred sulfonated polyester polyols have melting points between 30° C and 80° C, most preferred between 40° C and 60° C. Especially preferred arc sulfonated polyester polyols prepared by reacting sulfonatc diacids or diols widi short chain diols and short chain diacids or derivatives of diacids. Examples of useful diols include ethylene glycol or condensates of cthylcneglycols, butanediol, butencdiol, propancdiol, ncopcntylglycol, hexanediol, 1 ,4-cyclohcxanc dimethanol, 1 ,2-propylcnc glycol and 2-mcdιyl- 1,3-propancdiol. Examples of useful diacids include adipic, azelaic, succinic, suberic acids, and phdialic acid. Examples of useful sulfonatc diacids and diols include sulfoisophdialic acid (and sodium salt), sulfossucinic acid (and sodium salts), 1,4-dihydroxybutane sulfonic acid (and sodium salt) and succinaldehyde disodium bisulfite. Examples of commercially available sulfonated polyester polyols that arc useful in the compositions of the invention arc die "Rucoflcx XS" scries made by Ruco Polymer Corporation for H.B. Fuller. Rucoflcx XS- 5483-55 and Rucoflcx XS-5536-60 are sulfonated polyester polyols based on 5- sulfoisophthalic acid monosodium salt (4 wt. % in XS-5483-55, and 6 wt. % in XS-5536-60), 1,6— hexanediol and adipic acid. See Table 5 below. 5- sulfoisophd alic acid monosodium salt is a cheaper key raw material for prcparing aqueous sulfonated polyurethane dispersions compared wid die sodium salt of N-(2-aminoethyl)-2-aminocthanc sulfonic acid as used in U.S. Patent 4,870,129. It contains an aromatic ring which will increase the heat resistance of the final resulting sulfonated polyurethane adhesives. Table 5. Composition of Rucoflcx SX-5484-55 and SX-5536-60 Rucoflcx adipic acid and 5-sulfoisophthalic 1,6-hcxanc did acid monosodium salt XS-5483-55 95% 4% XS-5536-60 94% 6% In accordance widi this invention, die sulfonated polyester polyol selected was reacted widi HDI or mixture of HDI wid odier diisocyanate at 70-90°C for 2-7 hours to prepare a prepolymcr containing sulfonate groups. The prepolymcr was dispersed into water, finally chain extended by EDA for example and/or chain terminators (e.g. EA). Surprisingly, the reaction between the sulfonated polyester polyol and HDI (or mixture of HDI and other diisocyanate) was found to be quite rapid. The reaction was carried out at 70-80°C just for 3-10 minutes, and d e reactant became a semi-solid or even a solid, which was difficult to dissolve into acetone. Therefore, an acetone process was used to prepare die sulfonate containing prepolymcr. The sulfonated polyester polyol was dehydrated in a vacuum at 100 °C. Acetone was added to dissolve it at 70-80°C, and HDI and other diisocyanate (e.g. TMXDI) were then added. The reaction was carried at 80-90°C for 3-5 hours. After dispersing and chain extension, d e acetone was d en immediately distilled off. About half die amount of acetone used in U.S. Pat. 4,870,129 was used in diis process. Thc resulting sulfonated aqueous polyuredianc dispersions possess stability at a low pH (5-7), in addition to high crystallization rate and low heat activation temperature. They have good compatibility with od er water-based polymers (e.g. vinyl acetate emulsion), and crosslinkcr (e.g. Bayer/Miles' Desmodour DA). The resulting adhesives exhibit high heat resistance. EXAMPLES The invention is furdier illustrated, but is not intended to be limited by die following examples in which all parts and percentages are by weight unless otherwise specified. Determination of Crystallization Rate DSC is used to measure the crystallization rale. The film samples made from aqueous polyurethane dispersion arc heated from -40 to 140°C at 10°C/minute. The resulting thermographies are "first run". The samples arc then quench cooled and reheated at 10°C/minute to produce d e thermographies arc "second run". Crystallization rate = DSC second run melting heat/ DSC first run melting heat. The results are shown in Table 4. Heat Activation Testing Drawdown polyurethane dispersion on a 10 mil clear PVC (poly vinyl cliloride film from Laird Plastics) with a #28 mylar rod. Dry to touch and cut into 1x6 inch strips. Seal the strips to uncoatcd 10 mil clear PVC using a Scntinal Heat Sealer at 50 psi nip pressure with a 30 second dwell time. Begin sealing at 125 °F, increasing die temperature 25 °F increments to 200°F. Allow laminates to age 15 minutes and determine peel strength at 12 inches per minute on an Intelcct 500. The results arc shown in Table 6 below for d e following Examples. Example 1 229 g. Rucoflcx XS-5483-55 (a sulfonated polyester polyol based on 5-sulfoisophthalic acid monosodium salt, adipic acid and 1,6-hcxancdiol, OH number 49.0) is dried in vacuo at 100°C. and d en dissolved into 250 ml. acetone at 70-80 °C. 21 g. 1,6-hcxanc-diisocyanalc (HDI) and 6.1 g. tctramcthylxylylene diisocyanate (TMXDI) arc added, whereupon die temperature is maintained at about 85° C. for 5 hours and dien cooled to about 50°C. At this temperature, the prepolymcr is dispersed by adding 389 g. water, and then chain extended by adding 2.4 g. cdiylcnediaminc (EDA) and 1.22 g. cdianolaminc (EA). The acetone is then immediately distilled off. A finely divided dispersion having a solids content of 40.7%, viscosity of 115 cps, particle size of 226 run and a pH of 11.2 is obtained. Example 2 343.5 g. Rucoflex XS-5483-55 is dried in vacuo at 100°C. and d cn 250 ml acetone, 30.24 g. HDI and 0.18 g. T-12 (dibutyltin dilaurate) are added into it at 70-80°C, whereupon the temperature is maintained at 80°C. for 2 hours. 10.98 g. TMXDI and 5.02 g. DMPA (dimcthylolpropionic acid) is added, keep the temperature at 85 °C. for anodicr 3 hours. During die reacting, additional 300 ml acetone is added to control the viscosity of die reactant. The temperature is cooled lo about 50°C, 600 g. water is added to disperse die prepolymcr, 5 minutes later 2.25 g. EDA (in 30 g. acetone) is added. The acetone is then immediately distilled off. A finely divided dispersion having a solids content of 39.3%, viscosity of 50 cps, and a pH of 6.41 is obtained. Examplc 3 229 g. Rucoflex XS-5483-55 is dried in vacuo at 100°C. and dicn 0.09 g. T-12, 250 ml acetone and 21.0 g. HDI are added into it at 80°C. After maintaining at 80°C. for 2 hours, 6.1 g. TMXDI and 150 ml acetone arc added, and keep die temperature at 85-90°C for another 3 hours. The temperature is cooled to about 50°C, 0.61 EA (ctlianolaminc) and 339 g. water first and then 2.7 g. EDA arc added into the prepolymcr acetone solution. The acetone is then immediately distilled off. A finely divided dispersion having a solids content of 40.14%, viscosity of 420 cps and a pl-l of 11.5 is obtained. Example 4 229 g. Rucoflcx XS-5483-55 is dried in vacuo at 100°C. and ti en 0.09 g. T-12, 1.0 g. DMPA, 22.58 g. HDI and 250 ml acetone are added at 80°C. After maintaining at 80°C for 2 hours, 6.56 g. TMXDI is added, and keep at 85-90°C for another 3 hours. The temperature is cooled to about 50°C, 393.5 g. water, 1.64 g. EA and 0.61 g. EDA (in 30 g. acetone) are added. The viscosity of the resulting dispersion is too high, additional 50 g. water is added. The acetone is then immediately distilled off. A finely divided dispersion having a solids contents of 35.16%, viscosity of 95 cps, particle size of 154 nm and a pH of 7.6 is obtained Example 5 229 g. Rucoflcx XS-5483-55 is dried in vacuo at 100°C, and then 1.34 g. DMPA, 0.09 g. T-12, 23.1 g. HDI, 2.69 g. TMXDI and 250 ml acetone arc added at 85 °C. After maintaining at 85 °C for 5 hours, d e temperature is cooled to about 50 °C, then 387 g. water, 0.7 g. EA and 1.62 g. EDA (in 50 g. water) arc added into die prepolymcr. The acetone is d cn immediately distilled off. A finely divided dispersion having a solids contents of 35.5%, viscosity of 515 cps, and a pH of 8.09 is obtained. Example 6 229 g. Rucoflcx XS-5483-55 is dried in vacuo at 100°C and dicn 1.34 g. DMPA, 23.1 g. HDI, 2.69 g. TMXDI, 0.09 g. T-12 and 250 ml acetone arc added at 85 °C. After maintaining at 85 °C for 5 hours, die temperature is cooled to about 50°C, then 386.98 g. water and 1.85 g. EDA arc added into the prepolymcr. The viscosity of the resulting dispersion is too high, additional 100 q. water is added. The acetone is dicn immediately distilled off. A finely divided dispersion having a solids content of 36.32%, viscosity of 104 cps, particle size of 117 nm and a pH of 7.45 is obtained. Example 7 229 g. Rucoflcx XS-5483-55 is dried in vacuo at 100°C, and d cn 0.09 g. T-12, 21.0 g. HDI and 450 ml acetone are added at 80°C. After maintaining at 80°C for 2 hours, 9.76 g. TMXDI is added, and die reaction is carried out at 85-90°C for another 3 hours. After die temperature is cooled to about 50°C, 397 g. water, 2.38 g. EA and 2.73 g. EDA (in 30 g. acetone and 20 g. water) are added into the prepolymcr. The acetone is dien immediately distilled off. A finely divided dispersion having a solids content of 35.75%, viscosity of 300 cps, particle size 198 nm and a pH of 10.95 is obtained. Example 8 114.5 g. Rucoflex XS-5483-55 and 50 g. Rucoflex S-102-55 (1- 6 butanediol adipate polyester polyol, OH No. 55) and 6.7 g. DMPA are dried in vacuo at 100°C, dien 17.64 g. HDI, 9.6 g. TEA (tricdiylaminc) and 50 ml acctone arc added at 75 °C. After maintaining at 80 °C for 2 hours, 12.2 g. TMXDI is added, and the reaction is carried out at 85-90°C for anodier 3 hours. The temperature is cooled to about 50 °C, 100 ml acetone is added, then 568.7 g. water and 1.8 g. EDA (in 35 ml acetone) arc added into the prepolymcr. After distilling acetone off, a finely divided dispersion is obtained. Example 9 200 g. Rucoflcx S-102-55 (Ruco's polyester polyol based on butanediol adipate, OH number 55.0) is dried in vacuo at 100°C, and dien 20.1 g. DMPA, 34.8 g. HDI and 14.4 TEA arc added at 70°C. After maintaining at 80°C for 2 hours, 24.4 g.TMXDI is added, the reaction is carried out at 90-100°C for another 3 hours. The temperature is cooled to 70°C, 150 ml acetone is added, and then 6.25 g. taurine and 4.58 g. EA in 790 g. water are added into the prepolymcr. After distilling acetone off, a finely divided dispersion is obtained. Example 10 181 g. Rucoflcx XS-5536-60 (a sulfonated polyester polyol based on 5-sufoisophthalic acid monosodium salt (6%), adipic acid and 1,6- hcxanediiol, OH number 61.9) is dried in vacuo at 100° C, and dien 1.0 g. DMPA, 0.08 g. T-12, 22.58 b. HDI and 200 ml acetone arc added at 80° C. After maintaining at 80° C for 2 hours, 6.50 g. TMXDI is added, the reaction is carried out at 85-90° C for another 3 hours. After the temperature is cooled to about 50° C, 422 g. water with 1.68 g. EA and 1.61 g. EDA arc added into d e prepolymcr. The acetone is then immediately distilled off. A finely divided dispersion having a solids content of 26.10%, viscosity of 60 cps, particle size 41 nm and a pH of 7.63 is obtained. Table 6 Example HDI/TMXDI EDA/EA Cry. Rate T-Peel (Kg) Activating at (°F) (Mol %) (Mol %) (%) 125 150 175 200 1 83/17 83/20 75.2 5.9 7.7 11.8 11.9 2 80/20 100/0 67.2 1.5 6.9 10.1 10.5 3 83/17 90/10 71.6 2.3 6.0 10.1 12.6 I 4 83/17 50/50 65.8 3.8 6.8 11.9 13.5 I 5 93/7 70/30 65.3 1.0 6.3 — 10.9 6 93/7 100/0 65.0 1.7 5.2 7.2 — 7 76/24 70/30 78.9 4.3 8.7 12.8 12.4 8 68/32 100/0 56.9 3.4 4.5 8.0 7.7 9 60/40 Taurine/EA 56.0 0.3 0.3 0.4 0.4 10 83/17 50/50 61.0 1.6 2.2 3.6 4.2 Whilc this invention may be embodied in many different forms, there arc described in detail herein specific preferred embodiments of d e invention. This description is an exemplification of the principles of the invention and is not intended to limit die invention to the particular embodiments illustrated. The above Examples and disclosure are intended to be illustrative and not exhaustive. These examples and description will suggest many variations and alternatives to one of ordinary skill in d is art. All these alternatives and variations arc intended to be included within the scope of die attached claims. Those familiar with the art may recognize other equivalents to die specific embodiments described herein which equivalents arc also intended to be encompassed by the claims attached hereto.

Claims: WHAT IS CLAIMED IS AS FOLLOWS: 1. A stable aqueous dispersion of anionic pdyurediane wherein the polyurcdiane comprises the reaction product of A and B as identified below: A. an isocyanatc terminated sulfonated prepolymcr prepared in die presence of acetone by reacting components (i) and (ii) wherein (i) is selected from the group consisting of a sulfonated polyester polyol, its mixture with dimcdiylol propionic acid (DMPA), its mixture with polyester polyol and DMPA, its mixture with polyethcr polyol and DMPA, its mixture with polyester- and polycdicr-polyol, and DMPA and mixtures thereof (ii) is selected from die group consisting of hexamethylenc diisocyanate (HDI), HDI mixed widi trimethylxylycnc diisocyanate (TMXDI), HDI mixed with anodicr aromatic diisocyanate, HDI mixed with anodicr aliphatic diisocyanate, and mixtures thereof to form a component which is dien reacted with B, optionally in the presence of triethylamine if the component is not in a salt form, in die presence of water wherein B. is selected from the group consisting of an aliphatic diamine, a cycloaliphatic diamine, an aromatic diamine, an aminoalcohol, ethylene diamine (EDA), EDA mixed with cthanolaminc, EDA mixed with taurine, EDA mixed with iscthionic acid, EDA mixed with N-isodccyloxypropyl-l,3-diaminopropane EDA mixed widi ureido diamine, and mixtures dicrcof. 2. The aqueous dispersion according to Claim 1 wherein die acetone is removed after die dispersion if formed. 3. A dispersion according to Claim 1 wherein the sulfonated polyester polyol is selected from one of the groups consisting of diacids, diols, sulfonate diacids, sulfonatc diols and mixtures thereof. 4. The dispersion according to Claim 3 wherein d e diacids and diols arc selected from the group consisting of aromatic and aliphatics. 5. The dispersion according to Claim 4 wherein die diacids are selected from the group consisting of adipic, azclaic, succinic, suberic and phdialic acids. 6. The dispersion according to Claim 4 wherein the diols arc selected from the group consisting of cthylcneglycol, condensates of cthyleneglycols, butanediol, butencdiol, propancdiol, ncopcntylglycol, hexanediol, 1 ,4-cyclohcxane dimethanol, 1,2-propylenc glycol and 2-mcthyl- 1,3-propanediol. 7. The dispersion according to Claim 3 wherein die sulfonatc diacids and sulfonatc diols are sulfoisophdialic acid, sulfosuccinic acid, 1,4- diliydroxy butane sulfonic acid and succinaldchydc disodium bisulfite. 8. The sulfonated polyester polyol is based on 5 -sulfoisophdialic acid monosodium salt, 1 ,6-hexancdiol and adipic acid. 9. The dispersion according to Claim 8 wherein the sulfonated polyester polyol has a molecular weight in the range of about 500 to 10,000 and a melting temperature in the range of about 10 to 100°C. 10. The dispersion according to Claim 9 wherein die molecular wcight range is about 1,000 to 4,000 and the melting temperature is about 40 to 60° C. 11. The dispersion of Claim 1 wherein the ratio of HDI mixed widi any of the second mentioned diisocyanatcs ranges from 100/0 to 0/100 by weight. 12. The dispersion of Claim 11 wherein the ratio ranges from 100/0 to 50/50 by weight. 13. The dispersion of Claim 1 including chain extender/chain terminators and wherein the ratio of chain extender to chain terminator ranges from 100/0 to 0/100 by weight. 14. The dispersion of Claim 13 wherein d e ratio ranges from about 50/50 to about 100/0. 15. A water dispcrsible polyurethane prepolymcr composition comprising die reaction product of components A and B, component A being selected from the group consisting of: a sulfonated polyester polyol, a sulfonated polyester polyol mixed wid dimcdiylol propionic acid (DMPA), a sulfonated polyester polyol mixed with another polyester polyol and DMPA, a sulfonated polyester polyol mixed with a polyester polyol and DMPA, and a sulfonated polyester polyol mixed with another polyester polycdier polyol and DMPA; component B being selected from die group consisting of: hexamcthylcne diisocyanate (HDI), HDI mixed wid tctramethylxylyenc (TMXDI), HDI mixed with an aromatic diisocyanate, HDI mixed with another aliphatic diisocyanate, and mixtures dicreof. 16. The prepolymcr of Claim 15 wherein die aromatic diisocyanate is toluene diisocyanate (TDI). 17. The prepolymcr of Claim 15 wherein die aromatic diisocyanate is 4,4' diphenylmcdiane diisocyanate (MDI). 18. The prepolymcr of Claim 15 wherein the aliphatic diisocyanate is isophonc diisocyanate (IPDI). 19. The prepolymcr of Claim 15 wherein the aliphatic diisocyanate is dicyclohexylmethane 4,4-diisocyanate (Hι 2 MDI). 20. The dispersion of Claim 15 wherein die ratio of HDI mixed with any of die second mentioned diisocyanatcs ranges from 100/0 to 0/100 by weight. 21. The dispersion of Claim 15 wherein die ratio ranges from 100/0 to 50/50 by weight. 22. The dispersion of Claim 15 wherein the ratio of chain extender to chain terminator ranges from 100/0 to 0/100 by weight. 23. The dispersion of Claim 15 wherein the ratio ranges from about 50/50 to about 100/0. 24. An aqueous polyurethane dispersion wherein the polyurcdiane comprises the reaction product of: a first reactant selected from die group consisting of: a sulfonated polyester polyol, a sulfonated polyester polyol mixed with dimethylol propionic acid (DMPA), a sulfonated polyester polyol mixed with another polyester polyol and DMPA and a sulfonated polyester polyol mixed with anodicr polyester polyedicr polyol and DMPA, and mixtures thereof; d e first reactant being reacted widi a component selected from d e group consisting of: hexamcthylcne diisocyanate (HDI), HDI mixed with tetrametliylxylyeiie diisocyanate (TMXDI), HDI mixed wid an aromatic diisocyanate, HDI mixed widi another aliphatic diisocyanate, and mixtures diereof, to form a prepolymcr, which in aqueous dispersion is caused to undergo further reaction wid a component selected from the group consisting of chain extenders, chain terminators and both chain extenders and chain terminators. 25. The dispersion of Claim 24 wherein the ratio of HDI mixed wid any of die second mentioned diisocyanates ranges from 100/0 to 0/100 by weight. 26. The dispersion of Claim 24 wherein the ratio ranges from 100/0 to 50/50 by weight. 27. The dispersion of Claim 24 wherein die ratio of chain extender to chain terminator ranges from 100/0 lo 0/100 by weight. 28. The dispersion of Claim 24 wherein the ratio ranges from about 50/50 to about 100/0. 29. An aqueous anionic polyurcdiane dispersion based on the reaction product of: (a) a polyol selected from the group consisting of a sulfonated polyester polyol or a polyol mixture including a sulfonated polyester polyol, and (b) a diisocyanate mixture including hexamethyylcnc diisocyanate (HDI) mixed widi a diisocyanate selected from the group consisting of tctaramcthylxylylene diisocyanate (TMXDI), aromatic diisocyanate and aliphatic diisocyanate to form a prepolymcr which is dispersed in water and caused to undergo cidicr chain extension, chain termination or both. 30. The dispersion of Claim 29 wherein die chain extender/ terminator is selected from the group consisting of aliphatic diamine, cycloaliphatic diamines, aromatic diamines, aminoalcohols and mixtures dicrcof. 31. The dispersion of Claim 29 wherein the ratio of HDI mixed wid any of d e second mentioned diisocyanatcs ranges from 100/0 to 0/100 by weight. 32. The dispersion of claim 29 wherein die ratio ranges from 100/0 to 50/50 by weight. 33. The dispersion of Claim 29 wherein die ratio of chain extender to chain terminator ranges from 100/0 to 0/100 by weight. 34. The dispersion of Claim 29 wherein the ratio ranges from 50/50 to about 100/0. 35. An aqueous anionic polyurethane dispersion based on die reaction product of: (a) a polyol selected from the group consisting of a sulfonated polyester polyol or a mixture diereof widi components selected from die further group consisting of dimcdiylol propionic acid (DMPA), polyester polyols and DMPA, pdyedier polyols and DMPA, and mixtures diereof, and (b) hexamethylenc diisocyanate (HDI) and its mixture widi anodicr diisocyanate selected from the group consisting of (TMXDI) tctramcthylxylylene diisocyanate, an aromatic diisocyanate or anodicr aliphatic diisocyanate to form a prepolymcr which is chain extended and/or chain terminated in forming the dispersion. 36. The dispersion of Claim 35 wherein die aromatic diisocyanate is selected from die group consisting of TDI, MDI and mixtures thereof. 37. The dispersion of Claim 35 wherein die another aliphatic diisocyanate is selected from the group consisting of IPDI, H 12 MDI and mixtures thereof. 38. The dispersion according to Claim 35 wherein the chain extender and chain terminator is comprised of ethylene diamine. 39. The dispersion of Claim 35 wherein die ratio of HDI mixed widi any of d e second mentioned diisocyanates ranges from 100/0 to 0/100 by weight. 40. The dispersion of Claim 35 wherein die ratio ranges from 100/0 to 50/50 by weight. 41. The dispersion of Claim 35 wherein die ratio of chain extender to chain terminator ranges from 100/0 to 0/100 by weight. 42. The dispersion of Claim 35 wherein the ratio ranges from about 50/50 to about 100/0. 43. An aqueous anionic polyurcdiane dispersion formed from a prepolymcr comprised of the reaction product of A and B as defined below wherein: A is selected from the group consisting of at least one sulfonated polyester polyol, a mixture of at least one sulfonated polyester polyol wid dimethylol propionic acid (DMPA), a mixture of at least one sulfonated polyester polyol with polyester polyol and DMPA, and a mixture of at least one sulfonated polyester polyol with polycdicr polyol and DMPA and mixtures thereof; B is selected from die group consisting of hcxamediylene diisocyanate (HDI), a mixture of HDI widi tctramediylxylylene diisocyanate (TMXDI), a mixture of HDI with an aromatic diisocyanate, a mixture of HDI with an aliphatic diisocyanate; and mixtures diereof, and the prepolymcr is dispersed in water wid a component C, and wherein C is a chain modifier selected from d e group consisting of cdiylencdiamine (EDA), a mixture of EDA widi taurinc, a mixture of cdianolamine (EA) with iscthionic acid or a mixture of EDA with N- isodccyloxy propyl-l,3-diaminopropanc, a mixture of EDA with Urcido diamine (imidazolidinone diamine). 44. The dispersion according to Claim 43 wherein the taurine is in salt form 45. The dispersion according to Claim 43 wherein d e iscdiionic acid is in salt form. 46. The aqueous anionic p yurediane dispersion of claim 43 wherein said aromatic diisocyanate is TDI or MDI. 47. The aqueous anionic polyurethane dispersion of claim 43 wherein said aliphatic diisocyanate is IPDI and H 12 MDI. 48. The dispersion of Claim 43 wherein the ratio of HDI mixed with any of the second mentioned diisocyanatcs ranges from 100/0 to 0/100 by weight. 49. The dispersion of Claim 43 wherein the ratio ranges from 100/0 to 50/50 by weight. 50. The dispersion of Claim 43 wherein die ratio of chain extender to chain terminator ranges from 100/0 to 0/100 by weight. 51. The dispersion of Claim 43 wherein die ratio ranges from about 50/50 to about 100/0. 52. A med od of preparing a stable aqueous dispersion of an ionic polyurcdiane comprising the steps of: (a) preparing an isocyanatc terminated sulfonated prepolymer in die presence of acetone from: (i) a polyol component selected from the group consisting of a sulfonated polyester polyol; a sulfonated polyester polyol mixed with dimethylol propionic acid (DMPA); a sulfonated polyester polyol mixed widi a polyester polyol and DMPA; a sulfonated polyester polyol mixed widi a polyctlier polyol and DMPA; and a sulfonated polyester polyol mixed with a polyester polyedier-polyol and DMPA; (ii) an isocyanate component selected from die group consisting of hexamcdiylcnc diisocyanate (HDI), HDI mixed with tetramethylxylene diisocyanate (TMXDI), HDI mixed with an aromatic diisocyanate and HDI mixed with another aliphatic diisocyanate, and (b) combining die prepolymer in water widi eid er a chain modifier selected from the group consisting of alkylene diamines, cthylcnediaminc (EDA), and a mixture of EDA with a compound from the further group consisting of ethanolaminc, taurinc, taurinc in salt form, iscdiionic acid, the salt of isethionic acid, N-isodccyloxypropy 1-1,3- diaminopropane (DA-14), and urcido diamine. 53. The method of Claim 52 wherein aromatic diisocyanate is selected from die group consisting of TDI and MDI. 54. The mcd od of Claim 52 wherein the aliphatic diisocyanate is selected from the group consisting of IPDI, and H 12 MDI. 55. The method of Claim 52 wherein the sulfonated polyester polyols are prepared from diacids, diols, sulfonatc diacids and/or sulfonatc diols. 56. The mcdiod of Claim 55 wherein the sulfonatc diacids and diols arc aromatic and aliphatic. 57. The mcdiod of Claim 52 wherein die sulfonated polyester polyol is prepared from 5-sulfoisophdιalic acid monosodium salt, 1,6-hexanediol and adipic acid. 58. The method of Claim 52 wherein the sulfonated polyester polyols have molecular weight of about 500-10000, and a melting point of about 10-100°C. 59. The mcdiod of Claim 52 wherein the sulfonated polyester polyols have molecular weight of about 1000-4000 and a melting point of about 40-60°C. • 60. The method of Claim 52 wherein (a) die polyol component is a sulfonated polyester polyol; (b) the diisocyanate component is selected from d e group consisting of HDI and mixtures of HDI; (c) die polyol is reacted widi the diisocyanate component at a temperature of about 70-90 °C for about 2-7 hours to prepare a prepolymer containing sulfonate groups; (d) die prepolymer is dispersed into water and combined widi chain extender and\or chain terminator. 61. The method of Claim 52 wherein the polyol and diisocyanate are reacted at a temperature of about 70-80°C for about 3-10 minutes, and die resulting high viscosity reactant is dissolved in acetone for further reacting die diisocyanate widi the polyol. 62. The method of Claim 61 wherein the polyol is dissolved in die acetone prior to reacting with the diisocyanate. 63. The method of Claim 52 wherein (a) the sulfonated polyester polyol is dehydrated in a vacuum at about 100°C and dissolved in acetone at a temperature of about 70-80°C; (b) die diisocyanate is added, after which die reaction is carried out at about 80-90°C for about 3-5 hours. (c) the prepolymcr is dispersed into water and combined with eid cr a chain extender, a chain terminator or both. (d) die acetone is distilled off. 64. The sulfonated aqueous polyurethane dispersion according to Claim 63 used in adhesives. 65. The sulfonated aqueous polyurethane dispersion according to Claim 63 in combination with other water-based polymers and crosslinkers. 66. The method of Claim 52 wherein the ratio of HDI mixed wid any of the second mentioned diisocyanatcs ranges from 100/0 to 0/100 by weight. 67. The mcdiod of Claim 52 wherein die ratio ranges from 100/0 to 50/50 by weight. 68. The method of Claim 52 wherein die ratio of chain extender to chain terminator ranges from 100/0 to 0/100 by weight. 69. The mediod of Claim 52 wherein die ratio ranges from about 50/50 to about 100/0.

Inventors: DOCHNIAK MICHAEL J, DUAN YOULU, STAMMLER SONJA, DOCHNIAK, MICHAEL, J., DUAN, YOULU, STAMMLER, SONJA
Applicants: FULLER H B LICENSING FINANC, H.B. FULLER LICENSING & FINANCING, INC.
Application year: 1994
Main classification: C08G18
IPC codes: C08G18, C08L75, C09J175